You are starting to make a name for yourself. Now word has reached you that Captain Kidd himself wants to meet you. Better sail to Tortuga and introduce yourself.

Mission Notes

As it says in the mission description: simply sail to Tortuga and talk to William Kidd. He'll be in the Crime Lord's Office - the entrance is a longboat, you have to click on it to be taken there. The NPCs that give you the pirate refit missions are in the same room.